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Objectives: Residual dissection of the brachiocephalic arteries after operations for acute type A dissection is considered a benign condition that does not expose patients to late neurologic events. This retrospective study, conducted on an outpatient clinic basis between June 1995 and May 2003, had the objectives of evaluating the consequences of residual dissection of the brachiocephalic arteries, investigating the long-term outcomes of patients with this condition, and illustrating our approach to the condition., Methods: Forty-two of 137 patients with spontaneous aortic dissection were identified as having residual dissection of the brachiocephalic arteries. There were 30 men and 12 women, with median age of 64.8 years. Patients were followed for a median time of 3.17 years (25th-75th percentile, 1.43-4.40 years; maximum, 7.5 years). The main outcome was the occurrence of cerebral ischemic events (transient ischemic attack or stroke) or death. The functional consequences of brachiocephalic artery dissection were studied by using duplex scanning and transcranial Doppler ultrasonography., Results: Twenty-four focal neurologic complications occurred in 13 of 42 patients (incidence, 30.9%); major strokes occurred in 6 patients, and none were fatal. Minor strokes occurred in 12 patients. In all patients the damaged territory was dependent on a dissected artery. Kaplan-Meier (90-months) freedom from focal neurologic events was 55.7% (95% confidence interval, 33.7%-72.9%). Mean time of freedom from focal neurologic events was 64.5 months (95% confidence interval, 53.1-75.9 months). Positive transcranial Doppler monitoring for microembolic signals was 24.1%, and patients with clinical symptoms had higher microembolic signal counts than did those without symptoms (8.4/h vs 1.9/h, P <.001). Reduced cerebrovascular reactivity to hypercapnia, calculated by using the breath-holding index values, was associated with severely impaired brachiocephalic artery perfusion. The multivariable model for predictors of late stroke (minor and major) included the following variables: microembolic signal count (1 signal/h increase; relative risk, 1.27 [95% CI, 1.12-1.77]), breath-holding index (0.10 increase; relative risk, 0.91 [95% CI, 0.87-0.94]), and the presence of at least one carotid axis with a thrombosed false channel (relative risk, 0.82 [95% CI, 0.64-0.93]). Sixteen operations were performed in 12 patients to relieve residual dissection., Conclusions: These results suggest an increased risk of ischemic events ipsilateral to the dissected arteries. Strict follow-up and identification of subjects at risk implies the exact knowledge of vessel anatomy and perfusion status. Ultrasonographic transcranial Doppler examination plays an important role in the clinical work-up of these patients.

Background: In aortic operations performed through a left thoracotomy, which require total bypass and deep hypothermic circulatory arrest, femoral artery cannulation is commonly used for arterial perfusion. This route limits the time of safe circulatory arrest and is associated with the risks of retrograde embolization or, in the case of aortic dissection, malperfusion of the vital organs. To overcome these problems, we have used cannulation of the extrathoracic left common carotid artery to ensure a central a route of arterial perfusion in these operations. The preliminary results are presented., Methods: Between December 1999 and April 2001, we used left common carotid artery cannulation in 26 operations on the thoracic aorta performed through a posterolateral thoracotomy with an open technique during deep hypothermic circulatory arrest. Institutional review board approval and informed consent were obtained. The indications included perforating atherosclerotic ulcer (n = 5), chronic aortic aneurysm (n = 9), acute type B aortic dissection (n = 3), and chronic dissection of the thoracic aorta (n = 9). Transcranial Doppler ultrasonographic monitoring of both the right and left middle cerebral arteries was used to assess the adequacy of cerebral bihemispheric perfusion and to determine the differences in blood flow velocities throughout the procedure., Results: Left common carotid artery cannulation was successful in all patients. All patients awoke from the operation, and none had cerebrovascular accidents. None died in the hospital, and complications related to carotid artery cannulation were not observed. None of the patients experienced postoperative paraplegia. In all patients transcranial Doppler monitoring indicated the absence of cerebral embolic phenomena throughout the entire procedure. Significant differences in middle cerebral artery flow velocities were observed at different phases of the procedures and between the right and left middle cerebral arteries during carotid cannulation and during selective cerebral perfusion. Nevertheless, the maximal drop of right middle cerebral artery blood velocity during selective perfusion through the left common carotid artery was within 50% of the left middle cerebral artery velocity, indicating adequate bihemispheric perfusion., Conclusions: In patients undergoing aortic operations through a left thoracotomy, extrathoracic left common carotid artery cannulation was a safe and effective means of providing proximal arterial inflow during cardiopulmonary bypass, which can be used to selectively perfuse the brain, as well as to prevent embolic phenomena in the arch vessels.

Background: Acute myocardial ischemia and infarction due to retrograde dissection of the aortic root reaching the coronary ostia is a potentially fatal condition. Surgical treatment of these patients relies on the re-establishment of an adequate coronary blood flow and on the rescue of jeopardized myocardium. This article reports the results of a selected group of 24 patients with type A acute aortic dissection and coronary artery dissection. We review our experience and illustrate our approach to this condition, which evolved over a 15-year period., Methods: Between July 1985 and March 2000, 24 patients from a total of 211 (11.3%) treated for acute type A aortic dissection had dissection of at least one of the coronary ostia. There were 14 men and 10 women. The mean age was 65.5 years (median 61.7; range 41-78 years). The right coronary artery was involved in 11 patients, the left in 4 patients, and both coronary arteries in 9 patients. At admission, 16 patients had Q waves (66%), inferior in 6 (25%) and anterior, lateral, septal, or posterior in 10 (41%). All procedures were done on an emergency basis within 10 hours (median 4 hours) after initial chest pain and within 2 hours after the patient's arrival., Results: Hospital mortality was 20% (5 patients); 3 patients could not be weaned from cardiopulmonary bypass and died intraoperatively, and 2 patients died postoperatively of low cardiac output., Conclusions: As illustrated in this study, direct coronary repair is a safe alternative to bypass grafting. Aggressive myocardial resuscitation together with early operation is a key factor in the management of these patients.

Background: With the progressive aging of Western populations, cardiac surgeons are faced with treating an increasing number of elderly patients. Controversy exists as to whether the expenditure of health care resources on the growing elderly populations represents a cost-effective approach to resource management. The potential to avoid surgery in patients with little chance of survival and poor quality of life would spare unnecessary suffering, reduce operative mortality, and enhance the use of scarce resources., Methods: We reviewed the records of 24 consecutive patients aged 80 years or older (mean age 83 years, range 80-93 years) who underwent operations for acute type A dissection from 1985 through 1999. No patient with acute type A dissection was refused surgery because of age or concomitant disease. Seventeen patients were men. Preoperatively, none of the patients was moribund, although 66% had hemodynamic instability and 41% experienced cerebral ischemia. All patients had one or more associated pathologic conditions. Hospital mortality and morbidity models, based on our overall experience with 197 patients operated on for acute type A aortic dissection during the period of the study, were developed by means of multivariate logistic regression with preoperative and intraoperative variables used as independent predictors of outcome., Results: Overall hospital mortality was 83%. Intraoperative mortality was 33%. All patients who survived the operation had one or more postoperative complications. Mean hospital stay was 37 days with a total of 314 days in the intensive care unit (average 19 days, median 17 days). None of the survivors (4 patients) discharged from the hospital was able to function independently and their survival at 6 months was 0%. Statistical analysis of the overall experience with operations for type A acute aortic dissection confirmed that age in excess of 80 years is the most important independent patient risk factor associated with 30-day mortality and morbidity., Conclusions: Operations for acute type A dissection performed on octogenarians involve increased hospital mortality and morbidity. Short-term survival is unfavorable and is associated with a poor quality of life. Without additional corroborative studies to endorse the present findings, the use of age as a parameter to limit access of patients to expensive medical resources remains an unsubstantiated concept. In the context of acute type A aortic dissection, however, the hypothesis that older patients should be denied such a complicated surgical intervention to conserve resources is supported by the presented data.

Background: Femoral arteries are the preferred site of peripheral cannulation for arterial inflow in type A aortic dissection operations. The presence of aortoiliac aneurysms, severe peripheral occlusive disease, atherosclerosis of the femoral vessels, and distal extension of the aortic dissection may preclude their utilization. Axillary artery cannulation may represent a valid alternative in these circumstances., Methods: Between January 15, 1989, and August 20, 1998, in our institution, 22 of 152 operations (14.4%) for acute type A aortic dissection were performed with the use of the axillary artery for the arterial inflow. Axillary artery cannulation was undertaken in the presence of femoral arteries bilaterally compromised by dissection in 12 patients (54.5%), abdominal aorta and peripheral aneurysm in 5 patients (22.7%), severe atherosclerosis of both femoral arteries in 3 patients (13. 6%), and aortoiliac occlusive disease in 2 patients (9.1%). In all patients, distal anastomosis was performed with an open technique after deep hypothermic circulatory arrest. Retrograde cerebral perfusion was used in 9 patients (40.9%)., Results: Axillary artery cannulation was successful in all patients. The left axillary artery was cannulated in 20 patients (90.9%), and the right axillary artery was cannulated in 2 patients (9.1%). Axillary artery cannulation followed an attempt of femoral artery cannulation in 15 patients (68. 2%). All patients survived the operation, and no patient had a cerebrovascular accident. No axillary artery thrombosis, no brachial plexus injury, and no intraoperative malperfusion were recorded in this series. Two patients (9.1%) died in the hospital of complications not related to axillary artery cannulation., Conclusions: In patients with type A aortic dissection in whom femoral arteries are acutely or chronically diseased, axillary artery cannulation represents a safe and effective means of providing arterial inflow during cardiopulmonary bypass.